Not authentic, but YUMMY. Take a pork picnic and slit holes all over like mentioned above and stuff with garlic. Take some GOYA SAZON seasoning packets and rob all over and in the nooks and crannies. This thing will look orangey yellow when you are done. Put in the oven at 325 for 5-8 hours. Take it out and face the fat side up and crank it to 425 until that skin crisps up. The smell is amazing, the seasoning is awesome. You can find the packets in the Hispanic foods isle. That stuff goes reall good sprinkled on rice too. So in review; stuff with garlic, rub with Goya and cook. Don't add slat and make sure to drain afterwards because there is a ton of fat on picnics.

My wife makes it with pork & or beef ! Best when cooked with the bone in !

That is a guisado or "guiso" -- slow cooked beef or pork in gravy. Carnitas are slow cooked for several hours in lard

Here's a pretty straightforward gringo recipe that will give you near authentic results http://www.youtube.com/watch?v=sx6svS1oxDE